diatoms are typical of newly setup tanks. I've had this in all of my S-T-S tanks. a quick remedy i've used is a powerhead with a filter attachment. Another more direct method was to use an aquarium vacuum attached to an airline running along the surface to siphon debris and diatoms. A third and last resort would be to do the one-two punch using hydrogen peroxide then excel...
The Aquatic Plant Society Curator of the NY/NJ/CT LFS & CO2 Directory
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